Asterisk art in python

Question

I would like to produce this picture in python!

         *
        **
       ***
      ****
     *****
    ******
   *******
  ********
 *********
**********         


        

Answer 1

 '%10s'    %'*'*x

is being parsed as

('%10s' % '*') * x

because the % and * operators have the same precedence and group left-to-right^[docs]. You need to add parentheses, like this:

x = 1
while x < 10:
    print '%10s' % ('*' * x)
    x = x + 1

If you want to loop through a range of numbers, it's considered more idiomatic to use a for loop than a while loop. Like this:

for x in range(1, 10):
    print '%10s' % ('*' * x)

for x in range(0, 10) is equivalent to for(int x = 0; x < 10; x++) in Java or C.

Answer 2

It's because of the operator precedence, use this one:

x=1
while x<10:
 print '%10s' % ('*'*x)
 x=x+1

Answer 3

To be exact, as your picture ends with 10 asterisks, you need.

for i in range(1, 11):
    print "%10s"%('*' *i)

Answer 4

print '\n'.join(' ' * (10 - i) + '*' * i for i in range(10))

Answer 5

string object has rjust and ljust methods for precisely this thing.

>>> n = 10
>>> for i in xrange(1,n+1):
...   print (i*'*').rjust(n)
... 
         *
        **
       ***
      ****
     *****
    ******
   *******
  ********
 *********
**********

or, alternatively:

>>> for i in reversed(xrange(n)):
...   print (i*' ').ljust(n, '*')
... 
         *
        **
       ***
      ****
     *****
    ******
   *******
  ********
 *********
**********

My second example uses a space character as the printable character, and * as the fill character.

The argument to ljust or rjust is the terminal width. I often use these for separating sections with headings when you have chatty debug printout, e.g. print '--Spam!'.ljust(80, '-').